You want a bit more bang, go for a 6.5 Grendel. Ammo starts at about .24 cents per shot (wolf steel case)to $1 per shot (hornady) pending on how precise you want to be. A 10.5" barreled 6.5 Grendel has more energy at the muzzle than a 20" hot-loaded 5.56 NATO, and it only separates from there in the Grendel's favor as the distance increases.

Neon,
You are at the point I was 2 yrs ago. Thought really hard about building a 300BO. What really caught my eye was the ability to suppress and cycling the action at the same time. I thought it would be perfect for hunting yada yada.

The more I researched, the more I came to the conclusion that silent hunting wasn't what I thought it would be. To stay subsonic you had to use heavy bullets, but at the speed they were running at, it was hit or miss if the bullet would be able to bring down an animal consistently, and it only went downhill when the distances increased. Too large a margin for me.

I will second the 6.5 Grendel. When it was first mentioned to me, I poo poo'd it, dinky little case driving a 6.5mm bullet slower than my .260. I didnt see any advantage to competing with a bullet going nearly 500fps slower than what my .260 could do.

Last year, my rifle club introduced AR tactical matches, AR type rifle with any caliber betw 223 and 308, using a Harris bipod and a squeezee bag, shot at 300, 500, and 600yds.

All of a sudden the Grendel looked more appealing to me, 6.5mm ballistics, in an AR type platform shot prone at a 1moa X ring.

I built an 18in with an 8twist barrel. I built it the way I did only because I did not want to wait wks or months for parts to be made. I bought from whoever had what I wanted at the time I wanted it.

All I can say is, it is a shooter, at 300yds and in no real advantage over a fast match 223. Where it really shines is beyond 300yds, the 6.5mm ballistics start pulling away from .223 especially if it is windy, less drift.

My rifle weighs in at just under 10lbs with my hunting scope, 11lbs with my match scope, that is with a loaded 5rnd mag and bipod.

Read my writeup on how it performed last Thanksgiving when I took it deer hunting in Tx, in the hunt/fish section. I stand by everything I said in that thread, lo recoil, excellent accuracy, the ability have a round ready if a followup shot was needed, in a package that was a lot more handy than my 24in hunting rifles.

My rifle is now coming up on nearly 1k rounds thru it, it is my preferred semi auto match setup. I really really like the Grendel.

Also have to mention that factory ammunition and reloading components are available for it at Bass Pro and Academy Sports.

SY

Tough times create strong people. Strong people create good times. Good times create weak people. Weak people create tough times.

People like to pooh-pooh the 300BLK for subsonic hunting due to it's heavy bullets, slow speed, rainbow trajectory, and limited killing ability past 100 yds. But, with the advanced selection of bullets out there, you can fund the right too for the job. I've never killed a deer or hog in Florida at more than 75 yds, and a Lehigh Defense Maximum Expansion load will hold a tight 1" group at 100 yds, will reliably expand to nearly double in diameter, and will retain 95%+ of their weight. Plus, you can swap out to supersonic loads and still use a suppressor then shoot deer out to 150-200 yds easily. The secret is figuring out your aiming points and hold overs with your optic.

Do what I did. Build a 300BLK upper. Shoot it on a lower that you already have. See what you think. If you end up falling out of love with the 300BLK, it's just a barrel swap away from something different. Me, I ended up building matching 5.56 (12") & 300BLK (10"") uppers, one rifle lower that I SBR'd, and one pistol lower. I swap them back and forth depending on my mood and the mission at hand.

Last edited by flcracker on Sun Jul 16, 2017 8:37 am, edited 1 time in total.

and some rin up hill and down dale, knapping the chucky stanes to pieces wi' hammers, like sae mony road-makers run daft - they say it is to see how the warld was made!

Neon besides just having a spare lower handy and the need to upper it, does this build have a particular purpose as your intent or desire is pertinent to the discussion? While the upper you linked seems to be a cost effective value it comes with it's own limitations as the flavor of the day in the 300 blk out world seems to be pistol gas and shorter barrels.

I got mine because I wanted something with a short barrel that didn't lose a crazy amount of FPS because it was short. I opted for a 10 1/2 inch barrel, but anything over 7 inch is GTG in the FPS range. Its very handy and and fast with a red dot and has become my preferred gun for when I'm beating around in the swamp or shooting short range targets. Yup, I think it's worth it.

I got a 300BLK upper recently to make a complete 22lr/223-5.56/300Blk uppers set with a single lower receiver for my son. I was thinking 300Blk with decent weight bullet and minimum recoil/muzzle blast might be the ideal hunting AR caliber for my 11 y/o son. So far I've shot one hog with it and despite a good hit on the neck and the hog dropped to the ground then while I was getting ready to come down from the stand the hog got up and ran off about 100 yards and died in neighbor's property hours later. I'm looking for a premium bullet (Barnes TSX or Hornady SST or AMAX) to try again. I've shot couple hogs with .223/5.56 and each of them dropped on the spot so I'm not impressed with this caliber but I'm willing to try again.

Fools learn from experience, intellegent person learns from experience of others.
She may not be of my flesh and blood but she is of my heart and soul.

rug357 wrote:I got a 300BLK upper recently to make a complete 22lr/223-5.56/300Blk uppers set with a single lower receiver for my son. I was thinking 300Blk with decent weight bullet and minimum recoil/muzzle blast might be the ideal hunting AR caliber for my 11 y/o son. So far I've shot one hog with it and despite a good hit on the neck and the hog dropped to the ground then while I was getting ready to come down from the stand the hog got up and ran off about 100 yards and died in neighbor's property hours later. I'm looking for a premium bullet (Barnes TSX or Hornady SST or AMAX) to try again. I've shot couple hogs with .223/5.56 and each of them dropped on the spot so I'm not impressed with this caliber but I'm willing to try again.

rug357 wrote:I got a 300BLK upper recently to make a complete 22lr/223-5.56/300Blk uppers set with a single lower receiver for my son. I was thinking 300Blk with decent weight bullet and minimum recoil/muzzle blast might be the ideal hunting AR caliber for my 11 y/o son. So far I've shot one hog with it and despite a good hit on the neck and the hog dropped to the ground then while I was getting ready to come down from the stand the hog got up and ran off about 100 yards and died in neighbor's property hours later. I'm looking for a premium bullet (Barnes TSX or Hornady SST or AMAX) to try again. I've shot couple hogs with .223/5.56 and each of them dropped on the spot so I'm not impressed with this caliber but I'm willing to try again.

Did you use Subsonic or supersonic ammo?

Supersonic ammo.

Fools learn from experience, intellegent person learns from experience of others.
She may not be of my flesh and blood but she is of my heart and soul.